On a hot Minnesota day in 2008, 12 year old Hailee LaMeyer took a swim in a lake near her home. Five days later, she was dead. Philip Gomph, an active 10 year old, went wakeboarding on Lake Arietta with his family in August 2009; a week later he died. The following year in 2010, young Will Mathews also died a week after wakeboarding in Louisiana. Between the years 2001 to 2010, there were 32 similar cases in the U.S. What exactly caused the sudden, tragic deaths of all these people? And why does it seem they all happened following water sport activities? “All it would’ve taken was for someone to educate me that this danger was out there,” said a heartbroken parent after the death of his 7 year old son Kyle, in 2010. “I would’ve changed the way we lived our lives with this information…I would’ve done what I needed to do as a parent to protect my kids.”
The invisible killer of these victims is Naegleria fowleri, an amoeba. This free-living amoeba can be pathogenic to humans and causes primary amebic meningoencephalitis (PAM), which is an inflammation of the brain. The amoeba’s food of choice is usually bacteria and yeast, however when it enters a human host it uses the food cup to eat tissues (such as brain tissue), as well as red and white blood cells.
Lurking places of this silent killer…
There are several places where N. fowleri amoebae like to live. This amoeba is a thermophile, meaning it enjoys high temperatures. It likes temperatures up to 45 degrees Celsius. The most common reservoir for this organism is freshwater, especially during the hot summer months; regularly found in lakes, ponds, mud puddles, slow flowing rivers, hot springs and soil such as sediment at the bottom of these freshwater sources.
It is also present in spas, swimming pools, well water, and municipal waters which are not properly chlorinated, as well as warm water flowing from industrial plants. Water heaters, cooling towers, and hydrothermal pools in hospitals are other places where it can grow. Basically wherever there is stagnant, warm water and shallow water beds, there will always be a chance that this little monster is present. When temperatures go down in fall and winter, there is obviously much less likelihood that the thermophile amoeba will be found in such water sources.
According to the CDC, N. fowleri is not found in salty water such as the ocean, which is good news for “ocean ducks” like swimmers and surfers in coastal states.
How it kills…
How exactly can one be infected with N. fowleri? The amoeba enters through the nose. The amoeba gets into the nose as water rushes up the nasal cavity when people go diving, swimming, water skiing, wakeboarding, or do other activities in freshwater where they submerge their head in the water or get water up their nose.
There have also been recent deaths from N. fowleri infection in the U.S., when two residents from different parts of Louisiana irrigated their sinuses using tap water instead of distilled water in neti pots. Researchers suggest that chemical signals used by nerve cells attract the N. fowleri amoeba once it’s in the nasal cavity. The amoeba breaks through the mucosa of the nasal cavity, travels up the olfactory nerves and then spreads to the brain and spinal cord. It seems that brain tissue is “accidental” food for this amoeba, since it prefers eating bacteria, but once it’s in the body, the brain is a convenient food option. The amoeba basically sucks brain cells.
According to the CDC, the fatality rate from infection by N. fowleri is over 99%, and there has been only 1 survivor out of 123 known infected people in the United States (CDC). Thankfully the infection cannot be transmitted from person to person, and neither is the infection acquired by drinking contaminated water. A few articles reporting on this amoebic infection pointed out that a lot of the cases occurred in people with the average age of 12, and 80% of cases among boys; however this rate may simply be because of the rough-and-tumble lifestyle and love of outdoor activities that boys at that age enjoy, increasing the chances of infection. No link has been reported to explain why it occurs mainly among boys.
The incubation period ranges between 3 to 7 days, or longer. Symptoms generally start with headaches, fever, nausea, and vomiting. It then rapidly progresses to neck stiffness, confusion, imbalance, seizures, hallucinations and coma, ultimately leading to death, sometimes in as little as 3 to 5 days after onset of symptoms. This infection is often confused with bacterial meningitis because diagnosis results and symptoms are similar to meningitis.
Unfortunately there is no effective treatment for a PAM infection. The most that can be done is administering Amphotericin B which is an antiprotozoan and antifungal drug, but it is not very successful, as evidenced by the 99% fatality rate from PAM. Unfortunately there are no vaccines currently available to protect against a PAM infection by this amoeba, nor is there any effort made to produce vaccines because the incidence of infection is so low compared to other diseases.
The most important thing to do is prevention of exposure to N. fowleri in the first place. This can be done by avoiding freshwater swimming spots in the summer, making sure swimming pools are properly chlorinated, keeping ones head out of the water if swimming in a lake or freshwater spot, or using nose clips if choosing to dunk underwater or participating in activities like boating and water skiing. Also, avoiding stirring up sediment from warm, stagnant freshwater is important. At home, people should avoid using tap water in sinus irrigating neti pots and avoid immersing head underwater in tap water. In some situations N. fowleri organisms can grow in home plumbing systems. Investigations were done at the homes of two amoeba infection cases in Louisiana who used tap water in sinus irrigation, and both their plumbing pipes tested positive for the amoeba. How it got in there is uncertain, but the CDC or other authorities have not established any formal recommendations on how to keep N. fowleri from getting in water pipes. In 2002, the CDC also found some wells in Arizona which contained untreated water and were harboring the amoeba. Two other people were affected with this brain eating amoeba infections from the well water.
Are there any measures taken to warn the public about places that could harbor the N. fowleri amoeba? Unfortunately, officials say it is difficult to implement guidelines because many things about this amoeba still remain unknown. There is no standardized test that can be used to check for N. fowleri in water (CDC). Some, such as families who have lost loved ones to brain eating amoeba infections, wish that the health department would post warning signs about N. fowleri near bodies of water to inform people of the possible risk. However, the CDC refuses to do so, explaining that it could generate misconceptions that bodies of water containing no warning signs are free of the organism. Furthermore, they say, the amount or location of amoeba in a body of water can fluctuate over time.
Concerned parents of children who have died from PAM infections feel this issue should be given more attention and health authorities should take action to prevent further tragedies. The Lewis family, parents of previously mentioned 7-year-old Kyle who died in 2010, have started an awareness foundation in honor of their son, the Kyle Lewis Amoeba Foundation. They hold seminars, spread brochures, share their testimony and stories from other families on their website, and work to inform parents and the general population of the danger of N. fowleri. They are also pushing a petition to make PAM a Nationally Notifiable Disease, which would require all states to report PAM infection cases to health authorities. Florida is the only state that presently reports it, while the rest of the states are not required to report (Kyle Lewis Amoeba Awareness Foundation). Mr. Lewis believes that most of the public is unaware of the danger, remembering his own painful introduction to the deadly infection when his son died, and realizing afterward that he could have prevented it quite easily if someone would have informed him. He reveals his frustration with the fact that little is being done by saying: “How many more kids is it going to take before we stop calling it ‘rare’?”
What can you do about it?
So protect yourselves and your children this summer! If you are going to spend time at a lake or body of freshwater, make sure you don’t get water up your nose. Use nose clips or simply stay away. Better be safe than sorry. Warn other friends and family of this potential danger. You never know if you saved a life. Spread awareness.